Why I . . . photograph nature

Why Nature Chose Selenium.

The authors were asked by the Editors of ACS Chemical Biology to write an article titled "Why Nature Chose Selenium" for the occasion of the upcoming bicentennial of the discovery of selenium by the Swedish chemist Jöns Jacob Berzelius in 1817 and styled after the famous work of Frank Westheimer on the biological chemistry of phosphate [Westheimer, F. H. (1987) Why Nature Chose Phosphates, Scie...

A Musical Photograph?

Why Do I Smoke and Why Do I Keep Smoking?

Shortly after smoking their last cigarette, smokers start to feel a negative mood change. This “withdrawal” from the chemical nicotine makes the smoker uncomfortable. Many smokers report feeling anxious, irritable and restless when they stop smoking. This is because they are not getting what the brain feels it needs to work well. Smokers usually experience relief from these unpleasant feelings ...

Atically Qpti Er- I. I Ntroducti on Fig. 1. Photograph of 30 Dof Hyper-redundant Robot

“Hyper-redundant” robots have a very large or infinite degree of kinematic redundancy. This paper develops new methods for determining “optimal” hyper-redundant manipulator configurations based on a continuum formulation of kinematics. This formulation uses a backbone curve model to capture the robot’s essential macroscopic geometric features. The calculus of variations is used to develop diffe...

Why nature chose a - amino acids *

The autocatalytic system, N-phospho-a-amino acids, could not only self-assemble into oligo-peptides but also act as the phosphorylation reagents to phosphorylate the nucleosides into nucleotides and oligo-nucleotides, in aqueous medium. While, the b-amino acids did not have such properties.